Beam combining for highlight projection

ABSTRACT

A novel projection system includes first and second light sources (e.g., sets of lasers), a spatial light modulator (SLM) that receives light from the first light source, and a beam steering device that receives light from the second light source and steers the light to highlight regions of the SLM. The SLM then modulates the light from both light sources to generate a highlighted imaging beam which can then be projected on a viewing surface. The highlighted imaging beam can represent a highlighted 2D image or a highlighted left- or right-eye view of a 3D image. The projection system thus improves peak brightness in the displayed highlighted images without incorporating a separate highlight projector or other expensive equipment. Methods for highlighting projected images are also described.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is continuation of U.S. patent application Ser. No.16/326,889, filed Feb. 20, 2019, which is U.S. National Stage ofInternational Application No. PCT/US2017/054088, filed Sep. 28, 2017,which claims the benefit of U.S. Provisional Application No. 62/402,365,filed Sep. 30, 2016 and European Patent Application No. 16198406.7,filed Nov. 11, 2016, each of which is hereby incorporated by referencein its entirety.

BACKGROUND Technical Field

This invention relates generally to image projection systems andmethods, and more particularly to image projection systems and methodsthat improve highlights in projected images.

Description of the Background Art

Video projection systems for use in movie theaters (cinemas) and hometheaters are known. While home theater systems usually are capable ofdisplaying only two-dimensional (2D) images, projection systems in movietheaters are often capable of displaying three-dimensional (3D) video.3D projection systems are very complex and thus expensive. Theyrepresent a significant capital investment for the cinema, especially ifthe 3D projection system is being used to show both 3D and 2D films andis operating in 2D mode a significant portion of the time.

It is also a goal of all projection systems to provide realisticimagery. An important component in realizing this goal is increasing thepeak brightness capable of being produced in the projected imagery. Forexample, most images will include both regions that are very bright(e.g., the sun) and areas that are very dim (e.g., objects in a shadow).Projections systems that have low peak brightness are not able torepresent such scenes very realistically, because the bright regions donot appear bright enough to the viewer. Brightness can be increased byadding a separate highlight projector to the projection system. However,the highlight projector represents a significant additional cost to themovie theater, especially in view of the already-expensive 3D projectionsystems, which often require multiple projectors. Furthermore, thehighlight projector must remain aligned with the main projector(s) forthe highlighted images to appear realistic and undistorted, which addsyet another on-going maintenance cost and time burden on the movietheater.

SUMMARY

The present invention overcomes the problems associated with the priorart by providing projection systems and methods that increase thebrightest parts (highlights) of the projected imagery with minimalcomplication and additional cost. Embodiments of the inventionfacilitate adding highlights to 2D images, as well as, adding highlightsto the individual left- and right-eye views of projected 3D images.

A projection system according to the invention includes an image datainput operative to receive image data, a first light source operative toemit a first illumination beam, and a second light source operative toemit a second illumination beam. Such a projection system also includesa spatial light modulator (SLM), which is disposed to receive light fromthe first light source and is operative to modulate the light from thefirst light source based on the image data to generate an imaging beam.A controller is coupled to receive the image data and is operative togenerate highlight data based on the image data, to provide the imagedata to the SLM, and to output the highlight data. A beam steeringdevice is coupled to receive the highlight data from the controller andis also disposed to selectively receive at least a portion of the secondillumination beam. The beam steering device steers the secondillumination beam to highlight regions of the SLM based on the highlightdata. Thus, the SLM also modulates light from the second light sourceaccording to the image data to impart highlights in the imaging beam.Projection optics are disposed in the path of the imaging beam and focusthe imaging beam on a viewing surface.

The image data can be 2D image data or 3D image data, and in someembodiments, the image data input is configured to sometimes receive 2Dimage data and at other times receive 3D image data, for example, basedon a 2D or 3D display mode. Accordingly, when the image data comprises2D image data, the controller receives the 2D image data, generates thehighlight data based on the 2D image data, provide the 2D image data tothe SLM, which then modulates the light from the first and second lightsources according to the 2D image data. Additionally, in the case of aprojection system capable of 3D, the first light source can beassociated with a first-eye view present in the image data when theimage data comprises 3D image data, the second light source can beassociated with a second-eye view present in the image data when theimage data comprises 3D image data, and the second light source can havedifferent spectral characteristics than the first light source. In otherembodiments, the projection system can include a polarization device(e.g., a light doubler, etc.) disposed in the path of the imaging beamand operative to impart a polarization state on the imaging beam.

In one particular embodiment, the projection system further includes asecond SLM and a redirector, where the second SLM is disposed to receivethe second illumination beam and modulate it based on the image data togenerate a second imaging beam. However, the redirector is disposed toreceive the second illumination beam and selectively redirect at leastsome of it to the beam steering device prior to the light from thesecond illumination beam reaching the second SLM. The power of thesecond illumination beam provided to the beam steering device can beapproximately 15% of the power of the first illumination beam.Additionally, in some embodiments the beam steering device includes aliquid crystal on silicon (LCOS) display, whereas in other embodiments,the beam steering device comprises a deformable mirror device (DMD).

Various light sources can be used with the invention. In one embodiment,the first light source includes a first set of primary lights (lasers),and the second light source includes a second set of primary lightshaving a different spectral composition than the first set of primarylights. In another embodiment, the first light source includes a firstwhite light source, and the second light source includes a second whitelight source, where the first white light has different wavelength bandsof red, green, and blue light than the second white light source. Insome embodiments, the controller is operative to cause the second lightsource/set of primary lights to be selectively energized responsive tothe image data being received on the image data input.

In particular embodiments, the projection system is a dual modulationsystem and includes a pre-modulator disposed in the path of the firstillumination beam that modulates the first illumination beam to generatea modulated first illumination beam. Even more particularly, the systemcan include a beam combiner (e.g., an optical thin film filter, etc.)that combines the modulated first illumination beam and the secondillumination beam to generate a combined illumination beam and providesthe combined illumination beam to the SLM. Additionally, the controllercan model a light field incident on the SLM based on the modulated firstillumination beam (and optionally the highlight data), and then adjustthe image data based on the modeled light field prior to providing theimage data to the SLM. In yet another embodiment, the beam combiner canbe located before the pre-modulator and combine the first illuminationbeam and the steered illumination beam, and output a combined modulationbeam to the pre-modulator.

A method for displaying image data with a projection system having afirst light source and a second light source is also disclosed. Such amethod includes the steps of receiving image data to be displayed by anSLM, generating highlight data based on the image data, illuminating theSLM with light from the first light source, illuminating a beam steeringdevice with light from the second light source, asserting the highlightdata on the beam steering device to steer the light from the secondlight source to highlight regions of the SLM based on the highlightdata, and asserting the image data on the SLM to modulate the light fromthe first light source and the light from the second light source togenerate a highlighted imaging beam.

The image data can be 2D image data or 3D image data. Additionally, insome methods, the step of receiving image data can include sometimesreceiving 2D image data and other times receiving 3D image data, forexample, based on a 2D or 3D display mode. In such a case, a particularmethod can include illuminating the beam steering device with light fromthe second light source responsive to receiving the 2D image data. Inother methods, such as those associated with a 3D-capable projectionsystem, the first light source can be associated with a first-eye viewpresent in the image data when the image data comprises 3D image data,the second light source can be associated with a second-eye view presentin the image data when the image data comprises 3D image data, and thesecond light source can have different spectral characteristics than thefirst light source. Still other methods include polarizing thehighlighted imaging beam (e.g., with a light doubler, etc.), forexample, to facilitate separation of the left- and right-eye views.

Some methods include dual modulation, which can include modulating thelight from the first light source with a pre-modulator to generate amodulated illumination beam prior to the step of illuminating the SLM.The method can also include the steps of combining the modulatedillumination beam and the light from the second light source that issteered by the beam steering device to generate a combined illuminationbeam, and illuminating the SLM with the combined illumination beam. Asanother option, a light field incident on the SLM can be modeled basedon the modulated illumination beam and, optionally, the highlight data,and the image data can be adjusted based on the modeled light fieldprior to asserting the image data on the SLM.

Still another particular method includes the steps of illuminating asecond SLM configured to have the image data asserted thereon with lightfrom the second light source, and redirecting at least some of the lightfrom the second light source to the beam steering device prior to thelight from the second light source reaching the second SLM.

A 3D projection system according to another embodiment of the inventionprovides highlighted left-eye and/or right-eye 3D views. The 3Dprojection system includes an image data input operative to receive 3Dimage data, a first light source, a second light source, a firstprojector, and a second projector. The first projector includes an SLMdisposed to receive light from the first light source and is operativeto modulate the light from the first light source based on the 3D imagedata to generate a first imaging beam associated with a first-eye viewpresent in the 3D image data. The first projector also includes acontroller coupled to receive at least a portion of the 3D image dataassociated with the first-eye view and operative to generate highlightdata based on the 3D image data associated with the first-eye view, toprovide the 3D image data associated with the first-eye view to the SLM,and to output the highlight data. A beam steering device of the firstprojector is coupled to receive the highlight data from the controller,is disposed to receive light from the second light source, and isoperative to steer the light from the second light source to highlightregions of the SLM based on the highlight data. Accordingly, the SLMalso modulates light from the second light source according to the 3Dimage data associated with the first-eye view and thus impartshighlights in the first imaging beam. Projection optics disposed in thepath of the first imaging beam focus the first imaging beam on a viewingsurface. Additionally, a first polarization device (e.g., a lightdoubler) disposed in the path of the first imaging beam imparts a firstpolarization state on the first imaging beam. In this embodiment, thesecond projector generates a second imaging beam associated with asecond-eye view present in the 3-D image data, such that the secondimaging beam has a second polarization state different than (e.g.,orthogonal to) the first polarization state. Optionally, the secondprojector can also impart highlights in the second imaging beam.

A method providing highlighted views in a 3D projection system includesthe steps of receiving 3D image data to be displayed by a first SLM,generating a first highlighted imaging beam associated with a first-eyeview present in the 3D image data, polarizing the first highlightedimaging beam in a first polarization state, generating a second imagingbeam (which can optionally be highlighted) associated with a second-eyeview present in the 3D image, and polarizing the second highlightedimaging beam in a second polarization state different than the firstpolarization state. The first highlighted imaging beam can be generatedby generating first highlight data based on the 3D image data associatedwith the first-eye view, illuminating the first SLM with light from thefirst light source, illuminating a beam steering device with light froma second source, using the beam steering device to steer the light fromthe second light source to highlight regions of the first SLM based onthe highlight data, and asserting the 3D image data associated with thefirst-eye view on the first SLM to modulate light from the first lightsource and light from the second light source.

Other methods for displaying 2D image data with a 3D projection systemare disclosed, where the 3D projection system has first and second lightsources of different spectral composition that are associated withfirst- and second-eye views present in 3D image data, respectively. Onesuch method includes the steps of receiving image data to be displayedby an SLM, determining whether the image data comprises 3D image data or2D image data, asserting the image data on the SLM, illuminating the SLMwith light from the first light source, and if the image data isdetermined to be 2D image data, causing the SLM to be furtherilluminated by light from the second light source. Another such methodincludes the steps of receiving image data to be displayed by an SLM,asserting the image data on the SLM, illuminating the SLM with anillumination beam from one of the first light source and the secondlight source, determining whether the image data is 3D image data or 2Dimage data, and if the image data is determined to be 2D image data,causing at least a portion of the illumination beam to be redirectedfrom the SLM to a second SLM configured to have the 2D image dataasserted thereon.

A method of manufacturing a projection system according to the inventionincludes the steps of providing a first light source, providing a secondlight source, providing an SLM disposed to receive light from at leastone of the first light source and the second light source and beingoperative to modulate light to generate an imaging beam, providing abeam steering device that is disposed to receive light from the secondlight source and that is operative to controllably steer light from thesecond light source toward selected regions of the SLM, and providing abeam combiner that is disposed to receive the light from the first lightsource and the steered light from the beam steering device and that isoperative to combine the light from the first light source and thesteered light from the second light source and provide the combinedlight to the SLM. A more particular method includes the step ofproviding a polarization device disposed in an imaging beam path of theSLM.

Non-transitory, electronically readable storage medium having codeembodied thereon for causing an electronic device to perform variousmethods of the invention are also disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is described with reference to the followingdrawings, wherein like reference numbers denote substantially similarelements:

FIG. 1 shows a 3D projection system 100 according to one embodiment ofthe present invention;

FIG. 2A shows the 3D projection system of FIG. 1 in greater detail andoperating in 3D mode;

FIG. 2B shows the 3D projection system of FIG. 2A operating in 2D mode;

FIG. 3 shows the left-eye projector of FIGS. 2A and 2B in greaterdetail;

FIG. 4 shows the controller of FIG. 3 in greater detail;

FIG. 5A shows a 3D projection system according to another embodiment ofthe invention and operating in 3D mode;

FIG. 5B shows the 3D projection system of FIG. 5A operating in 2D mode;

FIG. 6 shows the left-eye projector of FIGS. 5A-5B in greater detail;

FIG. 7 shows the redirector and right-eye projector of FIGS. 5A-5B ingreater detail;

FIG. 8 shows the controller of FIG. 7 in greater detail;

FIG. 9 shows a 3D projection system according to yet another embodimentof the invention;

FIG. 10 shows a 3D projection system according to still anotherembodiment of the invention;

FIG. 11 shows the left-eye projector of FIG. 10 in greater detail;

FIG. 12 is a flowchart summarizing a method for displaying 2D image datawith a 3D projection system according to the invention;

FIG. 13 is a flowchart summarizing a method for providing highlighted 3Dviews in a 3D projection system according to the invention;

FIG. 14 is a flowchart summarizing another method for displaying 2Dimage data with a 3D projection system according to the invention;

FIG. 15 is a flowchart summarizing yet another method for displaying 2Dimage data with a 3D projection system according to the invention; and

FIG. 16 is a flowchart summarizing a method of manufacturing aprojection system according the present invention.

DETAILED DESCRIPTION

The present invention overcomes the problems associated with the priorart by providing projection systems and methods that increase thebrightest parts (highlights) of the projected imagery with minimalcomplication and additional cost. In the following description, numerousspecific details are set forth (e.g., particular control modules,particular highlighting routines, etc.) in order to provide a thoroughunderstanding of the invention. Those skilled in the art will recognize,however, that the invention may be practiced apart from these specificdetails. In other instances, details of well-known projection practices(e.g., modulator control, routine optimization, etc.) and componentshave been omitted, so as not to unnecessarily obscure the presentinvention.

FIG. 1 is a block diagram showing a three-dimensional (3D) projectionsystem 100 according to one embodiment of the present invention. 3Dprojection system 100 includes a left-eye projection system (LEPS) 102and a right-eye projection system (REPS) 104, which are served media(e.g., 2D or 3D video and image content) from a media server 106. LEPS102 and REPS 104 project images onto a viewing screen 108 (e.g., a highgain screen, etc.) for viewing by an audience. LEPS 102 and REPS 104 arepositioned at different locations within a theater, but their projectedimages are aligned (registered) with each other on viewing screen 108 sothe audience perceives only one image.

LEPS 102 and REPS 104 can operate in either 3D or 2D mode, depending onthe media that they are served by media server 106. In 3D mode, LEPS 102projects a left-eye image and REPS 104 projects a right-eye image, whichare present in the 3D media provided from media server 106. Media server106 can serve video that is left-eye and right-eye specific to each ofLEPS 102 and REPS 104, or it can serve combined 3D video data, and LEPS102 and REPS 104 can parse the combined 3D video data into left- andright-eye image data themselves.

In this embodiment, projection system 100 provides spectral separationof the left- and right-eye images to facilitate 3D viewing.Specifically, LEPS 102 employs a first set of primary light sourceshaving spectral bands R1, G1, and B1, whereas REPS 104 employs a secondset of primary light sources having spectral bands R2, G2, B2. Becausethe spectral bands of LEPS 102 and REPS 104 are different (e.g.,comprise different wavelengths in the red, green, and blue regions ofthe visible spectrum), the left-eye and right-eye images can bedifferentiated when viewed by the audience through spectral 3D glasses110. The 3D glasses 110 includes a left-eye lens 112, which includes anoptical filter that passes the R1, G1, B1 bands but blocks the R2, G2,B2 bands, and a right-eye lens 114, which passes the R2, G2, B2 bandsbut blocks the R1, G1, B1 bands. Thus, the wearer of 3D glasses 110views left-eye and right-eye images projected by LEPS 102 and REPS 104through the left-eye lens 112 and right-eye lens 114, respectively, andperceives a 3D image.

In 2D mode, LEPS 102 and REPS 104 project a series of 2D images onviewing screen 108 according to the 2D media provided by media server106. LEPS 102 and REPS 104 can display a series of frames of 2D media inany convenient way, such as each displaying the same frame of the 2Dmedia at the same time, displaying frames of the 2D media sequentiallyin alternation, etc. Because 2D media is not intended for 3D viewing,spectral glasses 110 are not used in 2D mode such that each eye of theviewer will observe light that is output by each of LEPS 102 and REPS104. Thus, as will be discussed below in various embodiments, LEPS 102and/or REPS 104 can utilize the lights of the other of REPS 104 and LEPS102 to add highlighting to the 2D images, thereby improving thebrightness of the projected 2D images and making them appear morerealistic to the viewing audience.

It should be noted at the outset that the following description of thepresent invention will often be made with respect to 3D projectionsystems that are adding highlights to projected 2D images when operatingin a 2D mode, because such an embodiment provides particular advantages.However, it should be understood that the highlighting componentry andmethods described herein are equally applicable to dedicated 2Dprojection systems (i.e., those incapable of projecting 3D).Additionally, embodiments will be described where highlighting is addedto each of the left-eye and right-eye views of projected 3D imagery.

FIG. 2A is a block diagram showing 3D projector system 100 in greaterdetail and operating in 3D mode. Accordingly, 3D video (image) data isprovided to LEPS 102 and REPS 104.

LEPS 102 is shown in greater detail to include a set of left-eye lasers(LELs) 202, a left-eye projector 204, and projection optics 206. LELs202 are laser light sources that provide a first illumination beam 208having a first spectral composition (e.g., R1, G1, B1) to left-eyeprojector 204. In some embodiments illumination beam 208 is provided asa composite beam and in other embodiments separate illumination beamsare provided for each of the discrete red, green, and blue channels.Left-eye projector 204 represents a projector kernel that housesmodulators and optics to modulate the illumination beam 208 according toleft-eye images present in the 3D video data and output a left-eyeimaging beam 210 for projection the left-eye onto viewing screen 108 viaprojection optics 206. Projection optics 206 focus the left-eye imagingbeam 210 on viewing screen 108.

Similarly, REPS 104 is shown in greater detail to include a set ofright-eye lasers (RELs) 212, a right-eye projector 214, and projectionoptics 216. RELs 212 are laser light sources that provide illuminationbeam(s) 218 having a second spectral composition (e.g., R2, G2, B2)different from the spectral composition of LELs 202. Right-eye projector214 represents a projector kernel that houses modulators and optics tomodulate the illumination beam 218 according to right-eye images presentin the 3D video data and output a right-eye imaging beam 220 forprojecting the right-eye images onto viewing screen 108 via projectionoptics 216. Projection optics 216 focus the left-eye imaging beam 220 onviewing screen 108.

FIG. 2A also shows that LEPS 102 includes some right-eye lasers 212H andthat REPS 104 includes some left-eye lasers 202H. RELs 212H and LELs202H have the same spectral compositions as RELs 204 and LELs 202,respectively, but are denoted with an “H” to indicate that they are usedfor adding highlights to the principal images projected by LEPS 102and/or REPs 104, respectively, when projection system 100 is operatingin 2D mode, as will be discussed in more detail below. However, the RELs212H and the LELs 202H are not powered in 3D mode in this embodiment dueto the spectral separation of the left-eye and right-eye images. Forexample, any highlighting added to the left-eye imaging beam 210 via theRELs 212H would be blocked by the left-eye lens 112 of glasses 110, andany highlighting added to the right-eye imaging beam 220 by the LELs202H would be blocked by the right-eye lens 114. (3D highlightingembodiments are discussed below.)

While LELs 202, 202H and RELs 212 and 212H are described herein aslasers, it should be understood that the light sources used by LEPs 102and REPs 104 can take various suitable forms. For example, LELs 202,202H and RELs 212, 212H can be replaced with white light sources havingdifferent red, green, and blue spectral bands, respectively. As anotheroption, LED arrays having different spectral characteristics could beprovided as the light sources.

FIG. 2B shows 3D projection system 100 operating in 2D mode.Accordingly, 2D video (image) data is provided to LEPS 102 and REPS 104from media server 106. Because no separation of the images provided byLEPS 102 and REPS 104 is required in 2D mode, viewers in the audience donot need to wear 3D glasses 110.

In 2D mode, the RELs 212H of LEPS 102 provide a second illumination beam238 (e.g., separate beams for each of the three primary color bands, acomposite white beam having spectral composition R2, B2, G2, etc.) toleft-eye projector 204. Projector 204 utilizes the light from RELs 212Hto add highlighting to regions of the principal image generated byleft-eye projector 204 based on the 2D image data. Accordingly,projection optics 206 outputs a highlighted imaging beam 240 fordisplaying a highlighted 2D image on viewing screen 108. Similarly, LELs202H of REPS 104 provide a second illumination beam 248 for right-eyeprojector 214 to use to add highlighting to regions of the principalimage generated by right-eye projector 214 based on the 2D image data.Projection optics 216 then outputs a highlighted imaging beam 250 fordisplaying a highlighted 2D image on viewing screen 108. As will bedescribed in more detail below, the highlighting increases the peakbrightness and improves the realism of the projected images.

In this embodiment, the laser power of RELs 212H that are added toleft-eye projection system 102 is approximately 15% of the total laserpower of LELs 202. Similarly, the laser power of LELs 202H that areadded to right-eye projection system 104 is approximately 15% of thetotal laser power of RELs 212. The inventors have found that this smallincrease in laser power can increase the brightness levels in thehighlighted regions of the imaging beams 240 and 250 by more than 10times the maximum brightness levels obtainable using the LELs 202 andRELs 212 alone. For example, in an existing projection system thatproduces a maximum brightness of 108 nits in 2D mode, the inventorsfound that adding RELs 212H and LELs 202H to the system and implementingthe highlighting disclosed herein increased the peak brightness of theprojection system to more than 1000 nits. Thus, the invention improvesthe realism of the displayed 2D images by increasing their peakbrightness to well above the peak brightness capabilities of aprojection system without LELs 202H, RELs 212H, and the inventivehighlighting capabilities.

FIG. 3 is a block diagram showing the left-eye projector 204 (FIGS.2A-2B) of LEPS 102 in greater detail. FIG. 3 will be described assumingthat LEPS 102 and left-eye projector 204 are operating in 2D mode suchthat highlighting is applied. It should further be understood that theright-eye projector 214 (FIGS. 2A-2B) of REPS 104 will havesubstantially the same componentry as that shown for left-eye projector204.

Left-eye projector 204 is shown to include one or more pre-modulators302, one or more beam steering devices 304, one or more beam combiners306, and one or more primary modulators 308. While FIG. 3 is shown withonly one of each of the above elements for simplicity, it will beunderstood that left-eye projector 204 will include a pre-modulator 302,a beam steering device 304, a beam combiner 306, and a primary modulator308 for each of the red, blue, and green color channels. Additionally,while FIG. 3 shows light beams passing through the above elements forsimplicity, in some embodiments light may actually be reflected off theelement instead. Finally, the functions of the elements of FIG. 3 willsometimes be described in the singular for simplicity. However, itshould be understood that this functionality is common to each iteration(e.g., across each color channel) of the element.

Pre-modulators 302 comprise a plurality of reflective spatial lightmodulators (SLMs) 302 (one for each primary color of LELs 202). In someembodiments, pre-modulators 302 can be embodied on a Philips prism,which provides separation of the constituent colors of a composite whitelight beam, should illumination beam 208 be provided as such. Left-eyeprojector 204 utilizes pre-modulators 302 for dual modulation purposes,which increases the dynamic range of the projected images bypre-attenuating portions of the illumination beam that are associatedwith darker regions of an image. Accordingly, each pre-modulator 302modulates an associated illumination beam 208 with an illuminationpattern based on the control signals and illumination data provided bycontroller 310, to generate a modulated illumination beam 312.Optionally, the colored modulated illumination beams 312 can berecombined into a single modulated illumination beam 312. In aparticular embodiment, pre-modulator 302 comprises a deformable mirrordevice (DMD), for example at a resolution of 2048×1080 pixels (2K).However, other types of SLMs, such as a liquid crystal on silicon (LCOS)device, can be used. Pre-modulators 302 can also be implemented as partof an illumination optics stage of projector 204, which contains otherlight conditioning elements.

Beam steering devices 304 also comprise a plurality of reflectivespatial light modulators 304 (e.g., one for each primary color of RELs212H) and can optionally be embodied on a Philips prism as well. Eachbeam steering device 304 receives highlight data from controller 310indicative of regions on primary modulator 308 to be highlighted, andbased on the highlight data, steers light in the illumination beam 238so that it will eventually impinge on the regions of primary modulator308 to be highlighted. Accordingly, beam steering device 304 outputs asteered illumination beam 314, which is provided to beam combiner 306.

Beam steering device 304 can be implemented using a phase-retardingmodulator. For example, a liquid crystal device (e.g., a reflective LCOSdevice) that selectively changes the phase of portions of illuminationbeam 238 can be used, whereby light from illumination beam 238 can besteered (e.g., on a pixel-by-pixel basis, on a region-by-region basis,etc.) to impinge on the regions of primary modulator 308 that areselected for highlighting. In a particular embodiment, the LCOS beamsteering device 304 has 2K resolution. As another example, beam steeringdevice 304 can be implemented using a phase-retarding DMD. As stillanother example, beam steering device 304 can be implemented using anarray of mirrors (e.g., 100×100 mirrors) that are able to tilt aroundtwo axes to steer the incident light in the desired directions.

Beam combiner 306 receives both modulated illumination beam 312 frompre-modulator 302 and steered illumination beam 314 from beam steeringdevice 304, combines the two beams, and outputs a combined illuminationbeam 316 to primary modulator 308. In one embodiment, beam combiner 306is implemented as part of a point-spread function (PSF) optics sectionof projector 204 that receives the various illumination beams as inputsand then outputs a desired light field (e.g., blurred and collimatedlight) to primary modulator 308 as the combined illumination beam 316.Because PSF optics sections of 3D projectors are typically serviceableand upgradable, existing 3D projectors can be readily and inexpensivelyretrofitted with beam steering devices 304 and beam combiners 306. Thus,the invention provides this advantage in addition to the improvedbrightness discussed above.

Optionally, beam combiner 306 can be disposed prior to pre-modulator302. In such an embodiment, beam combiner 306 can receive illuminationbeam 208 from LELs 202 and steered illumination beam 314 from beamsteering device 304, combine them, and provide a combined illuminationbeam to pre-modulator 302. Alternatively, in the case where dualmodulation and pre-modulator 302 are not utilized, beam combiner 306could provide the combined illumination beam directly to primarymodulator 308.

In a particular embodiment, beam combiner 306 comprises a dichroic beamcombiner that enables light from LELs 202 and light from RELs 212H to becombined. This can be accomplished with beam combiners 306 for thediscrete red, green, and blue channels as mentioned above. In the caseof white light, a beam combiner 306 can be implemented using an opticalthin film filter(s) similar to 3D glasses 110.

Primary modulator 308 receives the combined illumination beam 316, whichis formed from both modulated illumination beam 312 and steeredillumination beam 314 from beam combiner 306, and modulates combinedillumination beam 316 according to the 2D image data and control signalsasserted thereon by controller 310. This modulation infuses the lightwith both an image that is present in the 2D image data as well ashighlight regions based on the steered illumination beam 314, therebygenerating highlighted imaging beam 240. Projection optics 206 thenfocuses highlighted imaging beam 240 on viewing surface 108. In aparticular embodiment, primary modulator 308 comprises a DMD, forexample with a 4096×2160 (4K) resolution.

Controller 310 provides overall coordination and control for the variouselements of FIG. 3. For example, controller 310 provides illuminationdata and control signals to pre-modulator 302 via control path 330.Similarly, controller 310 provides adjusted image data and controlsignals to primary modulator 309 via control path 332. Furthermore,controller 310 determines highlight data based on the input image data,and provides the highlight data and control signals to beam steeringdevice 304 via control path 334. Controller 310 can also selectivelyenergize LELs 202 and RELs 212H via control path(s) 336.

It should be noted that highlighting can be provided using LEPS 102 andREPS 104 at the same time, in alternation, or from only one of LEPS 102and REPS 104 as desirable based on a particular application.Additionally, if localized heating of a primary modulator (e.g., primarymodulator 308) limits the amount of highlighting achievable by one ofLEPS 102 and REPS 104, then both of LEPS 102 and REPS 104 can be used toapproximately double the maximum brightness of highlights in aparticular image region, while reducing the local heating on eachindividual primary modulator.

It should also be noted here that the componentry shown in FIG. 3 canalternatively be embodied in a dedicated 2D projection system thatgenerates only two-dimensional imagery. In such a case, REPS 104 can beeliminated because a dedicated 2D projection system does not require thecapability to generate individual left-eye and right-eye views requiredfor 3D. Also, the LELs 202 and RELs 212H shown in FIG. 3 can beimplemented as two light sources in the dedicated 2D projector havingthe same or different spectral characteristics, again because theability to distinguish between left-eye and right-eye views is notrequired. Accordingly, the present invention can provide imagehighlighting and its associated advantages in a projection systemcapable of displaying only 2D images.

FIG. 4 is a block diagram showing controller 310 (FIG. 3) in greaterdetail according to a particular embodiment of the invention. Controller310 includes a mode detect module 402, a light source control module404, an illumination data and control module 406, a light field modeler408, an image data and control module 410, and a highlight data andcontrol module 412. The modules and associated functionality ofcontroller 310 can be implemented using hardware, software, firmware, orsome combination thereof. Accordingly, it should be understood thatleft-eye projector 204 and/or LEPS 102 can include one or moreprocessing units, working memory (e.g., RAM), and non-volatile datastorage (e.g., hard disk drives, solid state memory, etc.) to implementthe described functionality. In a particular embodiment, thefunctionality of the modules of controller 310 is implemented bysoftware being executed on processor(s) and in RAM of left-eye projector204. Accordingly, code for these software modules can be stored in anon-transitory medium (e.g., non-volatile data storage), even whenleft-eye projector 204 is powered down.

Mode detect module 402 enables left-eye projector 204 to determine if itis operating in 2D or 3D mode. Here, module 402 detects the mode basedon the image data input to controller 310, for example, using headerinformation, a data format, etc. that is present in the image data.Alternatively, media server 106 could notify mode detect module 402 ofthe desired display mode based on the type of data (2D or 3D) that mediaserver 106 provides. Mode detect module 402 then notifies light sourcecontrol module 404 of the display mode via communication pathway 414.Mode detect module 402 further communicates the display mode and/orimage data to the other modules of controller 310 via communicationpathway 416.

Light source control module 404 controls the LELs 202 and the RELs 212Haccording to the display mode. In 3D mode, module 404 causes only theLELs 202 to be energized. However, in 2D mode, module 404 causes boththe LELs 202 and the RELs 212H to be energized, so that highlighting canbe added to the 2D images.

Illumination and data control module 406 receives the image data,analyzes the image data, and then outputs pre-modulation data andcontrol signals to pre-modulator 302, so that pre-modulator 302 willmodulate illumination beam 208 in the desired way. In this embodiment,left-eye projector 204 is a dual modulation projector, which facilitatesincreased dynamic range. For example, using the input image data, module406 can determine which pixels of primary modulator 308 will bedisplaying darker regions of an image. Accordingly, module 406 cangenerate and provide illumination data to pre-modulator 302 such thatpre-modulator 302 will attenuate the portions of illumination beam 208that are associated with the darker regions of the image. Thispre-modulation, in turn, decreases the amount of required attenuation byprimary modulator 308 in those darker regions. As a result, the lightoutput of dark pixels of primary modulator 308 will be closer to 0%,which improves the dynamic range of left-eye projector 204.

In the present example, illumination data and control module 406operates the same in 2D and 3D modes. However, in other embodiments,module 406 could generate illumination data so that pre-modulator 302modulates the illumination beam 208 based on any expected highlighting.As another option, for example where the illumination beam 208 and thesteered illumination beam 314 are combined prior to pre-modulation andpre-modulator 302 receives a combined illumination beam, illuminationdata and control module 406 could generate illumination data forpre-modulator based on the highlighting.

The illumination data and/or control signals generated by illuminationdata and control module 406 are also provided to light field modeler408. Light field modeler 408 utilizes the illumination data to determinehow an associated pre-modulator 302 will modulate the illumination beam208 and, based on this analysis, generates a model of the light fieldthat will impinge on an associated primary modulator 308. The modeledlight field represents the light that will be impinging on themodulating surface of primary modulator 308. Light field modeler 408then outputs the modeled light field to image and data control module410.

In one embodiment, light field module 408 operates the same in both 2Dand 3D mode. In an alternative embodiment, light field modeler 408 cantake the highlights expected to be provided on primary modulator 308 bysteered illumination beam 314 into account when determining the lightfield.

Image data and control module 410 receives the modeled light field andthe image data, and then adjusts the image data based on the modeledlight field. For example, in this dual modulation embodiment, module 410can adjust the image data associated with the darker regions of theimage to compensate for the diminished light field in those darkerregions as a result of the pre-modulation in both 2D and 3D modes.

In 2D mode, highlight data and control module 412 generates highlightdata based on the 2D image data and provides the generated highlightdata to beam steering device 304. The highlight data gets asserted onbeam steering device 304, which causes device 304 to steer the lightfrom illumination beam 238 in the desired directions toward thehighlight regions. Module 412 can use any desired method to generate thehighlight data. For example, based on the image data, module 412 canidentify all pixels that have an intensity value above a predefinedthreshold (e.g., above 90% of maximum), and then generate highlight datathat causes beam steering device 304 to steer light to the regions ofprimary modulator 308 corresponding to the identified pixels. As anotheroption, module 412 can divide the image into a plurality of predefinedregions associated with primary modulator 308, identify a predeterminednumber of the brightest predefined regions, and then generate highlightdata that causes beam steering device 304 to steer light to theidentified regions of primary modulator 308. These are only twoexamples. The highlighting routines employed by module 412 can beadjusted based on the desired application and based on the type of beamsteering device 304 that is used.

In this embodiment, highlight data and control module 412 is inoperativein 3D mode. However, in later embodiments described herein wherehighlighting is provided in 3D mode, highlight data and control module412 can generate highlight data to highlight one or both of a left-eyeview and a right-eye view.

It should also be noted that a feedback 418 is shown in FIG. 4 fromhighlight data and control module 412 to light field modeler 408. Iffeedback 418 is used, light field modeler 408 can take the generatedhighlight data into account when determining the light field to provideto image data and control module 410. This feedback can help decreasethe black level (i.e., improve the contrast) of small dark regionslocated in a region of primary modulator 308 that is being highlightedby beam steering device 304. As another option, feedback 418 can beprovided to illumination data and control module 406 if it is desiredthat module 406 determine illumination data based on the highlight datagenerated by module 412. This could be useful, for example, where beamcombiner 306 is disposed prior to pre-modulator 302.

Finally, the functionality of the elements shown in FIG. 4 can beadjusted as appropriate in the case of the dedicated 2D projectionsystem described. For example, in a dedicated 2D projection system, themode detect module 402 can be eliminated, because there is only onemode. This and other possible modifications will be apparent based onthe particular projection system in which the highlighting features ofthe present invention are being implemented.

FIG. 5A is a block diagram showing a projection system 500, according toan alternative embodiment of the invention, operating in 3D mode.Projection system 500 includes a left-eye projection system (LEPS) 502and a right-eye projection system (REPS) 504. LEPS 502 includes a set ofleft-eye lasers (LELs) 506, a left-eye projector 508, and projectionoptics 510. REPS 504 includes a set of right-eye lasers (RELs) 512, aredirector 514, a right-eye projector 516, and projection optics 518.

LEPS 502 is configured to operate in a 3D or 2D mode depending on thetype of video data provided by a media server (not shown). In FIG. 5A,LEPS 502 is operating in a 3D mode due to 3D video data received on itsdata input. Left-eye projector 508 modulates light from LELs 506 togenerate a left-eye imaging beam 520, which is projected onto viewingscreen 522 via projection optics 510. As in projector system 100, LELs506 produce light in a first set of red, green, and blue spectral bands(e.g., R1, G1, and B1).

REPS 504 is also configured to operate in a 3D or 2D mode depending onthe type of video data provided by the media server. In 3D mode,redirector 514 passes all of the light from RELs 512 to right-eyeprojector 516. Right-eye projector 516 modulates light from RELs 512 togenerate a right-eye imaging beam 524, which is projected onto viewingscreen 522 via projection optics 518. RELs 512 produce light in a secondset of red, green, and blue spectral bands (e.g., R2, G2, and B2), whichare different than the spectral bands of LELs 506. As in projectionsystem 100, these different spectral bands facilitate spectralseparation of the left- and right-eye views by audience members wearingspectral 3D glasses 526, which are similar to the 3D glasses 110discussed previously.

FIG. 5B shows projection system 500 operating in 2D mode. Accordingly,LEPS 502 and REPS 504 are receiving 2D image data on their inputs.Because projection system 500 is operating in 2D mode, redirector 514 isredirecting some of the laser light (approximately 15% in this instance)to LEPS 502 via a light path 530. The remainder of the light from RELs512 (e.g., approximately 85%) is transferred to right-eye projector 516.Projector 508 modulates the light it receives from LELs 506 along withthe light it receives from RELs 512 via light path 530, and generateshighlighted 2D images on viewing screen 522 via highlighted imaging beam540. Projector 516 of REPS 504 also modulates the remainder of the lightit receives from RELs 512 via redirector 514 and projects un-highlighted2D images on screen 522 via a second imaging beam 550. In thisembodiment, only the images from LEPS 502 include highlighting. However,in other embodiments where LEPS 502 also includes a redirector, REPS 504can be configured to generate highlighted images. As above, in 2D mode,no glasses are needed for viewing.

FIG. 6 is a block diagram showing left-eye projector 508 (FIGS. 5A-5B)in greater detail. Projector 508 includes a pre-modulator 602, a beamsteering device 604, a beam combiner 606, a primary modulator 608, and acontroller 610. These components operate similarly to the correspondingcomponents of FIG. 3, except that beam steering device 604 receiveslight from RELs 512 via optical path 530. Like in FIG. 3, apre-modulator 602, a beam steering device 604, a beam combiner 606, anda primary modulator 608 are shown for only one color channel of left-eyeprojector 508. However, it will be understood that left-eye projector508 will include iterations of these components for each color band(e.g., one for red, one for green, and one for blue.) Additionally,while light paths are shown traversing optical elements, it will beunderstood that reflective optical elements (e.g., pre-modulators 602,beam steering devices 604, and primary modulators 608, etc.) can beused.

FIG. 7 is a block diagram showing redirector 514 and right-eye projector516 of FIGS. 5A-5B in greater detail. Here redirector 714 is implementedto redirect a desired amount of light (e.g., 0-15%, etc.) from RELs 512to LEPS 502. Accordingly, the rest of the light (e.g., 85-100%, etc.) istransferred to right-eye projector 516. In a particular embodiment,redirector 714 comprises mechanically-switched mirrors that move in andout of the path of the illumination beam from RELs 512 to selectivelytransfer light to optical path 530. Light can be transferred betweenRELS 512 and LEPS 502 via optical path 530 using free-space beams,switched fiber optic cables, etc.

FIG. 7 further shows that right-eye projector 516 includes apre-modulator 702, PSF optics 704, a primary modulator 706, projectionoptics 518, and a controller 710. Pre-modulator 702, primary modulator706, and projection optics 518 perform the same general functions as therelated elements described above in FIG. 6, with the exception thathighlighting are not provided by right-eye projector 516. Additionally,PSF optics 704 provide a desired light field to primary modulator 706but, in this embodiment, does not include a beam combiner. In analternative embodiment, however, light from LELs 506 can be transferredto right-eye projector 516 and right-eye projector 516 can include thecomponents shown in FIG. 6 to implement highlighting of 2D imaging beam550. Finally, controller 710 provides control and coordination ofpre-modulator 702, primary modulator 706, redirector 514, and RELs 512via respective data and control paths 730, 732, and 736.

FIG. 8 is a block diagram showing controller 710 in greater detailaccording to an exemplary embodiment of the invention. Controller 710includes a mode detect module 802, a redirector and light source controlmodule 804, an illumination data and control module 806, a light fieldmodeler 808, and an image data and control module 810. The modules andassociated functionality of controller 810 can be implemented usinghardware, software, firmware, or some combination thereof as describedabove with respect to controller 310.

Mode detect module 802 enables right-eye projector 516 to determine ifit is operating in 2D or 3D mode. Mode detect module 802 notifies lightsource control module 804 of the display mode via communication pathway814. Mode detect module 802 further communicates the display mode and/orimage data to the other modules of controller 710 via communicationpathway 816.

Redirector and light source control module 804 controls redirector 714and, optionally, RELs 512. When mode detect module 802 indicates 2Dmode, module 804 causes redirector 514 to transfer light from RELs 512to LEPS 502 via optical path 530. Module 804 can also turn RELs 512 onand off at the appropriate times (e.g., when 2D or 3D image data ispresent on the video data input right-eye projector 514, etc.).

Illumination and data control module 806 receives the image data,analyzes the image data, and then outputs illumination data and controlsignals to pre-modulator 702 via data and control path 730, so thatpre-modulator 702 will modulate the illumination beam from redirector514 in a desired way for dual modulation. In some embodiments, module806 utilizes the mode detection information from module 802 tooptionally adjust how light is modulated by pre-modulators 702. Forexample, module 806 might adjust how the illumination beam is modulatedby pre-modulators 702 to compensate for the light being transferred outof REPs 504 via optical path 730 in 2D mode.

The illumination data and/or control signals generated by module 806 arealso provided to light field modeler 808, which utilizes the data togenerate light field model representing the light that will impinge onthe modulating surface of primary modulator 706. Light field modeler 808outputs the modeled light field to image and data control module 410.Optionally, light field modeler 808 can adjust how it models the lightfield based on the display mode and expected illumination provided byRELs 512.

Image data and control module 810 receives the modeled light field andthe image data, and then adjusts the image data based on the modeledlight field. Module 410 generates adjusted image data in both 2D and 3Dmodes, and outputs the adjusted image data to primary modulator 706 viacontrol path 732.

FIGS. 5-8 illustrate an embodiment of the invention where LEPS 502 andREPS 504 can be inexpensively retrofitted for highlight projection. Forexample, the PSF optics section of LEPS 502 can be upgraded to includebeam steering device 604 and/or beam combiner 606 along with a port foradmitting light via optical path 530. Similarly, REPS 504 can be readilymodified to include redirector 514 by upgrading its light source stage.Thus, the projection system shown in FIGS. 5-8 efficiently addshighlighting to the 2D images from LEPS 502 using light from an existinglight source of REPS 504. Any reduction in brightness in the imagesprojected by imaging beam 550 from REPs 504 due to such light transferis more than made up for by the increased peak brightness level of thehighlighted imagery from LEPS 502.

FIG. 9 is a block diagram showing a projection system 900 according toyet another embodiment of the invention. Projection system 900 canselectively operate in 3D or 2D modes, and its components are housedwithin the same projector housing 902. Projection system 900 includes acontroller 904, a set of left-eye lasers (LELs) 906 that emit a firstset of primary lights (e.g., R1, G1, B1) having first spectralcharacteristics, left pre-modulators 908, left beam steering devices910, left beam combiners 912, and left primary modulators 914.Projection system 900 also includes a set of right-eye lasers (RELs) 916that emit a second set of primary lights (e.g., R2, G2, B2) havingsecond spectral characteristics that are different (e.g., have differentspectral bands) than the spectral characteristics of LELs 906, rightpre-modulators 918, right beam steering devices 920, right beamcombiners 922, and right primary modulators 924.

Controller 904 implements 3D projection when 3D video (image) data isreceived on its data input 926. In 3D mode, the “left” componentsgenerate left-eye views of 3D images present in 3D image data asdescribed above with reference to FIGS. 2-4. Similarly, the “right”components generate right-eye views of 3D images present in the 3D imagedata in the same way. Controller 904 drives the components of projectionsystem 900 to cause an imaging beam 928, comprising sequential left- andright-eye views, to be output by projection optics 930. As before,spectral 3D glasses 932 similar to spectral glasses 110 (FIG. 1) providespectral separation of the left- and right-eye views for viewers in theaudience.

Projection system 900 also includes a set of highlight RELs 916H and aset of highlight LELs 906H for highlighting 2D images in 2D mode.(Optionally, LELs 906H and RELs 916H can comprise designated ones ofLELs 906 and RELs 916, respectively, instead of additional lightsources.) When 2D images are displayed using the “left” componentry,controller 904 adds highlights to the 2D images by energizing RELs 916Hand controlling left beam steering devices 910 as described above inFIGS. 2-4. Similarly, when 2D images are displayed using the “right”componentry, controller 904 adds highlights to the 2D images byenergizing LELs 906H and controlling right beam steering devices 920 asdiscussed above. In some cases, the “left” and “right” componentry canbe driven in alternation in 2D mode so that any highlighting added tothe images do not overheat one of the primary modulators 914 and 924.Projection system 900 thus can selectively project 2D images withhighlights or 3D images from a single projector.

FIG. 10 is a block diagram showing a 3D projection system 1000 accordingto yet another embodiment of the invention. Projection system 1000facilitates highlighting each of the individual left-eye and right-eyeviews of a 3D image. 3D projection system 1000 can be a dedicated 3Dprojection system for only displaying 3D images, or alternatively, 3Dprojection system 1000 can also have the ability to display andselectively highlight 2D images. 3D projection system 1000 includes botha left-eye projection system (LEPS) 1002 and a right-eye projectionsystem (REPS) 1004, which generate left-eye and right-eye 3D views,respectively. LEPS 1002 includes two light sources 1006 and 1008. Lightsources 1006 and 1008 can be embodied in two sets of primary lights, twowhite light sources, etc. LEPS 1002 also includes a left-eye projector1010, left-eye projection optics 1012, and a left-eye polarizationdevice 1014. Left-eye projector 1010 houses modulators and optics thatmodulate the illumination beams 1016 and 1018 provided by light sources1006 and 1008, respectively, according to left-eye images present in the3D video data. Projector 101 also projects a left-eye imaging beam 1020,which is infused with the left-eye images, onto viewing screen 1022 viaprojection optics 1012 and a polarization device 1014. Projection optics1012 focus the left-eye imaging beam 1020 on viewing screen 1022.Polarization device 1014 imparts a first polarization state on theleft-eye imaging beam 1020, which is used for image separation.

REPS 1004 also includes two light sources 1024 and 1026. Light sources1024 and 1026 can be embodied in two sets of primary lights, two whitelight sources, etc. They can also be the same or different than thelight sources 1006 and 1008. In a particular embodiment, light sources1006 and 1024 comprise a first plurality of primary lights (e.g., R1,G1, B1) and light sources 1008 and 1026 comprise a second plurality ofprimary lights (e.g., R2, G2, B2), which have different red, green, andblue spectral bands than the first plurality of primary lights.

REPS 1004 also includes a right-eye projector 1028, right-eye projectionoptics 1030, and a right-eye polarization device 1032. Right-eyeprojector 1028 houses modulators and optics that modulate theillumination beams 1034 and 1036 provided by light sources 1024 and1026, respectively, according to right-eye images present in the 3Dvideo data. Projector 1028 also outputs a right-eye imaging beam 1040,which is infused with the right-eye images, for projection onto viewingscreen 1022 via right-eye projection optics 1030 and a right-eyepolarization device 1032. Right-eye projection optics 1030 focus theright-eye imaging beam 1040 on viewing screen 1022, and right-eyepolarization device 1032 imparts a second polarization state on theright-eye imaging beam 1040 that is orthogonal to the first polarizationstate of imaging beam 1020.

The orthogonal polarization states of imaging beams 1020 and 1040facilitate separation of the left-eye and right-eye views for theviewers in the audience. These orthogonal polarization states can beeither linear (e.g., vertical and horizontal) or circular (e.g., leftand right handed). Polarized 3D glasses 1042 are worn by the audiencemembers. The glasses 1042 have polarized lenses 1044 and 1046, with theleft-eye lens 1044 having the first polarization state and the right-eyelens 1046 having the second polarization state.

Because polarization of an imaging beam diminishes light outputsignificantly, each of the polarization devices 1014 and 1032 can be a“light doubler”. A light doubler is a device that splits an imaging beaminto two orthogonally-polarized beams, and then converts thepolarization of one of the split beams to match the other split beam.The split beams can then be projected as a one imaging beam with onepolarization state. One such light doubler is the “RealD XL” system madeby RealD. Accordingly, the orthogonal polarization states can beimparted on each of imaging beams 1020 and 1040 by respective lightdoublers 1014 and 1032, which increases the brightness perceived by theaudience.

As indicated above, the left-eye projector 1010 and the right-eyeprojector 1028 advantageously add highlights to the right-eye andleft-eye imaging beams 1020 and 1040, respectively. The addition of suchhighlights significantly increases the peak brightness of the left-eyeand right-eye views projected on viewing screen 1022 over a 3Dprojection system without highlighting as indicated above. This allowsmedia creators to develop image content that appears more realistic andpleasing to the viewers.

FIG. 11 is a block diagram showing left-eye projector 1010 (FIG. 10) ingreater detail according to an exemplary embodiment of the invention.The structure and operation of right-eye projector 1028 is substantiallysimilar to left-eye projector 1010, with the exceptions of thedifferences noted herein.

Left-eye projector 1010 includes a pre-modulator 1102, a beam steeringdevice 1104, a beam combiner 1106, a primary modulator 1108, and acontroller 1110. These components operate similarly to the correspondingcomponents of FIG. 3, except that pre-modulator 1102 and beam steeringdevice 1104 receive illumination beams 1016 and 1018 from first andsecond light sources 1006 and 1008, respectively. Like in FIG. 3, onlyone of each of pre-modulator 1102, beam steering device 1104, beamcombiner 1106, and primary modulator 1108 are shown for an exemplarycolor channel of left-eye projector 1010. However, it will be understoodthat left-eye projector 1010 can include multiple (e.g., 3) iterationsof these components for each color band (e.g., one for red, one forgreen, and one for blue) of the illumination beams 1016 and 1018.Additionally, while light paths are shown passing through somereflective optical elements (e.g., pre-modulators 1102, beam steeringdevices 1104, and primary modulators 1108, etc.), it will again beunderstood that these optical elements might instead reflect light fromtheir modulating surfaces.

The components of left-eye projector 1010 function as follows tofacilitate highlighting of desired regions of left-eye images present inimaging beam 1020. Controller 1110 selectively energizes light sources1006 and 1008 via a control path 1136 to selectively generateillumination beams 1016 and 1018, respectively. Pre-modulator 1102receives illumination data for each left-eye view from controller 1110via control path 1130 and modulates illumination beam 1016 accordinglyto generate a modulated illumination beam 1112. Beam steering device1104 receives highlight data generated by controller 1110 via controlpath 1134. Beam steering device 1104 also receives second illuminationbeam 1018 from second light source 1008, steers portions of theillumination beam 1018 (e.g., by phase retardation, etc.) toward desiredhighlight regions of primary modulator 1108, and outputs a steeredillumination beam 1114. Modulated illumination beam 1112 and steeredillumination beam 1114 are then combined by beam combiner 1106 andprovided to primary modulator 1108 as a combined illumination beam 1116.Primary modulator 1108 modulates the combined illumination beam 1116according to adjusted left-eye image data provided it from controller1110 on control path 1132. As in FIG. 4, the adjusted image data hasbeen generated based on a modeled light field associated with modulatedillumination beam 1112 and, optionally, further based on the highlightdata provided to beam steering device 1104. However, in this embodiment,the adjusted image data is associated with a left-eye view of a 3Dimage.

Primary modulator 1108 then outputs a highlighted, dual-modulatedimaging beam 1020 to projection optics 1012, where it is focused onviewing screen 1022 through polarization device 1014. As indicatedabove, polarization device 1014 imparts a first polarization state onimaging beam 1020, which is orthogonal to the polarization stateimparted on imaging beam 1040. In a particular embodiment, polarizationdevice 1014 is a “light doubler” device as described above.

Right-eye projector 1028 includes substantially the same components asleft-eye projector 1010. Accordingly, right-eye projector 1028facilitates the addition of highlights to right-eye images infused inright-eye imaging beam 1040. As mentioned above, right-eye imaging beam1040 is infused with an orthogonal polarization state as left-eyeimaging beam 1020, so that the left-eye and right-eye images (andassociated highlighting) can be resolved by polarized 3D glasses 1042

Methods of the present invention will now be described with reference toFIGS. 12-16. For the sake of clear explanation, these methods might bedescribed with reference to particular elements of thepreviously-described embodiments. However, it should be noted that otherelements, whether explicitly described herein or created in view of thepresent disclosure, could be substituted for those cited withoutdeparting from the scope of the present invention. Therefore, it shouldbe understood that the methods of the present invention are not limitedto any particular elements that perform any particular functions.Furthermore, some steps of the methods presented herein need notnecessarily occur in the order shown. For example, in some cases two ormore method steps may occur simultaneously. These and other variationsof the methods disclosed herein will be readily apparent, especially inview of the description of the present invention provided previouslyherein, and are considered to be within the full scope of the invention.

FIG. 12 is a flowchart summarizing an exemplary method 1200 fordisplaying image data with a projection system having a first lightsource and a second light source. In a first step 1202, image data to bedisplayed on a spatial light modulator (SLM) is received. Then, in asecond step 1204, highlight data is generated based on the image data.In a third step 1206, the SLM is illuminated with light from the firstlight source, and in a fourth step 1208, a beam steering device isilluminated with light from the second light source. In a fifth step1210, the highlight data is asserted on the beam steering device tosteer light from the second light source to highlight regions of the SLMbased on the highlight data. In a sixth step 1212, the image data isasserted on the SLM to modulate light from the first light source andlight from the second light source to generated a highlighted imagingbeam.

FIG. 13 is a flowchart summarizing an exemplary method 1300 forproviding highlighted views in a 3D projection system. In a first step1302, 3D image data to be displayed on an SLM is received, and in asecond step 1304, a highlighted imaging beam associated with a first-eyeview present in the 3D image data is generated. In a third step 1306,the highlighted beam is polarized in a first polarization state. In afourth step 1308, a second imaging beam associated with a second-eyeview present in the 3D image data is generated, and in a fifth step, thesecond imaging beam is polarized in a second polarization state that isdifferent (e.g., orthogonal to) the first polarization state.

The highlighted imaging beam can be generated by generating highlightdata based on a portion of the 3D image data associated with thefirst-eye view, illuminating the SLM with light from a first lightsource, illuminating a beam steering device with light from a secondlight source, using a beam steering device to steer light from thesecond light source to highlight regions of the SLM based on thehighlight data, and asserting 3D image data associated with thefirst-eye view on the SLM to modulate light from the first light sourceand light from the second light source to generate the highlightedimaging beam.

FIG. 14 is a flowchart summarizing a method 1400 for displaying 2D imagedata with a 3D projection system having a first light source associatedwith a first-eye view present in 3D image data and a second light sourceassociated with a second-eye view present in the 3D image data, wherethe first and second light sources have different spectralcharacteristics. In a first step 1402 image data to be displayed by anSLM is received, and in a second step 1404, the image data is assertedon the SLM. In a third step 1406, the SLM is illuminated by light fromthe first light source. In a fourth step 1408, it is determined whetherthe image data comprises 2D or 3D image data and, in a fifth step 1410,if the image data is determined to be 2D image data, then the SLM iscaused to be further illuminated by light from the second light source.However, if in fourth step 1408, it is determined that the image data is3D image data, then method 1400 ends.

FIG. 15 is a flowchart summarizing another method 1500 for displaying 2Dimage data with a 3D projection system having a first light sourceassociated with a first-eye view present in 3D image data and a secondlight source associated with a second-eye view present in 3D image data,where the first and second light sources have different spectralcharacteristics. In a first step 1502 image data to be displayed by anSLM is received, and in a second step 1504, the image data is assertedon the SLM. In a third step 1506, the SLM is illuminated with anillumination beam from one of the first light source and the secondlight source. In a fourth step 1508, it is determined whether the imagedata comprises 2D or 3D image data and, in a fifth step 1510, if theimage data is determined to be 2D image data, then at least a portion ofthe illumination beam is redirected from the SLM to a second SLMconfigured to have 2D image data asserted thereon. However, if in fourthstep 1508, it is determined that the image data is 3D image data, thenmethod 1500 ends.

FIG. 16 is a flowchart summarizing a method 1600 for manufacturing aprojection system according to the present invention. In a first step1602 a first light source is provided, and in a second step 1604 asecond light source is provided. In a third step 1606, a spatial lightmodulator (SLM) is provided, is disposed to receive light from at leastone of the first light source and the second light source, and isoperative to modulate light to generate an imaging beam. In a fourthstep 1608, a beam steering device is provided, is disposed to receivelight from the second light source, and is operative to controllablysteer light from the second light source toward selected regions of theSLM. In a fifth step 1610, a beam combiner is provided and is disposedto receive the light from the first light source and the steered lightfrom the beam steering device. The beam combiner is also operative tocombine the light from the first light source and the steered light fromthe second light source and provide the combined light to the SLM. In anoptional sixth step 1612, a polarization device (e.g., a light doubler)is provided and disposed in an imaging beam path of the SLM.

The description of particular embodiments of the present invention isnow complete. Many of the described features may be substituted, alteredor omitted without departing from the scope of the invention. Forexample, each projector can include a redirector (e.g., like redirector514) so that light from either left or right projectors can be input tothe other. As another example, alternative highlighting routines may beemployed (e.g., giving priority to highlighting in the center of theimage, etc.) in addition to, or as a substitute for, the ones describedabove. As still another example, the highlighting components androutines discussed herein can be implemented in a projection system thatis dedicated to displaying only 2D imagery. These and other deviationsfrom the particular embodiments shown will be apparent to those skilledin the art, particularly in view of the foregoing disclosure.

Various aspects of the present invention may be appreciated from thefollowing enumerated example embodiments (EEEs):

EEE 1. A projection system comprising:

-   -   an image data input operative to receive image data;    -   a first light source operative to emit a first illumination        beam;    -   a second light source operative to emit a second illumination        beam;    -   a spatial light modulator (SLM) disposed to receive light from        said first light source and being operative to modulate said        light from said first light source based on said image data to        generate an imaging beam;    -   a controller coupled to receive said image data and being        operative to generate highlight data based on said image data,        to provide said image data to said SLM, and to output said        highlight data;    -   a beam steering device coupled to receive said highlight data        from said controller, said beam steering device disposed to        receive at least a portion of said second illumination beam and        being operative to steer said second illumination beam to        highlight regions of said SLM based on said highlight data such        that said SLM also modulates light from said second light source        according to said image data to impart highlights in said        imaging beam; and    -   projection optics disposed in the path of said imaging beam and        operative to focus said imaging beam on a viewing surface.        EEE 2. The projection system of EEE 1, wherein:    -   said first light source comprises a first set of primary lasers;        and    -   said second light source comprises a second set of primary        lights having a different spectral composition than said first        set of primary lasers.        EEE 3. The projection system of EEE 1, wherein:    -   said first light source comprises a first white light source;    -   said second light source comprises a second white light source;        and    -   said first white light source and said second white light source        comprise different wavelength bands of red, green, and blue        light.        EEE 4. The projection system of EEE 1, wherein said controller        is operative to cause said second light source to be selectively        energized responsive to said image data being received on said        image data input.        EEE 5. The projection system of EEE 1, wherein the power of said        second illumination beam provided to said beam steering device        is approximately 15% of the power of said first illumination        beam.        EEE 6. The projection system of EEE 1, wherein said beam        steering device comprises a liquid crystal on silicon (LCOS)        display.        EEE 7. The projection system of EEE 1, wherein said beam        steering device comprises a deformable mirror device (DMD).        EEE 8. The projection system of EEE 1, further comprising a        pre-modulator disposed in the path of said first illumination        beam and being operative to modulate said first illumination        beam to generate a modulated first illumination beam.        EEE 9. The projection system of EEE 8, further comprising a beam        combiner disposed to receive said modulated first illumination        beam and said second illumination beam and being operative to        combine said modulated first illumination beam and said second        illumination beam to generate a combined illumination beam and        provide said combined illumination beam to said SLM.        EEE 10. The projection system of EEE 9, wherein said beam        combiner comprises an optical thin film filter.        EEE 11. The projection system of EEE 8, wherein said controller        is further operative to:    -   model a light field incident on said SLM based on said modulated        first illumination beam; and    -   adjust said image data based on said light field prior to        providing said 2D image data to said SLM.        EEE 12. The projection system of EEE 11, wherein said controller        is further operative to model said light field incident on said        SLM based on said highlight data.        EEE 13. The projection system of EEE 1, further comprising:    -   a second SLM disposed to receive light from said second light        source and operative to modulate said light from said second        light source based on said image data to generate a second        imaging beam; and    -   a redirector disposed to receive said second illumination beam        and selectively redirect some of said second illumination beam        to said beam steering device prior to light from said second        light source reaching said second SLM.        EEE 14. The projection system of EEE 1, wherein:    -   said image data input is configured to receive 3D image data or        2D image data;    -   said first light source is associated with a first-eye view        present in said image data when said image data comprises 3D        image data;    -   said second light source is associated with a second-eye view        present in said image data when said image data comprises 3D        image data; and    -   said second light source has different spectral characteristics        than said first light source.        EEE 15. The projection system of EEE 14, wherein:    -   when said image data comprises 2D image data, said controller        receives said 2D image data and is operative to generate said        highlight data based on said 2D image data and provide said 2D        image data to said SLM; and    -   when said image data comprises 2D image data, said SLM modulates        said light from said first light source and said light from said        second light source according to said 2D image data.        EEE 16. The projection system of EEE 1, wherein said image data        comprises 2D image data.        EEE 17. The projection system of EEE 1, wherein said image data        comprises 3D image data.        EEE 18. The projection system of EEE 1, further comprising a        polarization device disposed in the path of said imaging beam        and being operative to impart a polarization state on said        imaging beam.        EEE 19. The projection system of EEE 18, wherein said        polarization device comprises a light doubler.        EEE 20. A method for displaying image data with a projection        system having a first light source and a second light source,        said method comprising:    -   receiving image data to be displayed by a spatial light        modulator (SLM);    -   generating highlight data based on said image data;    -   illuminating said SLM with light from said first light source;    -   illuminating a beam steering device with light from said second        light source;    -   asserting said highlight data on said beam steering device to        steer said light from said second light source to highlight        regions of said SLM based on said highlight data; and    -   asserting said image data on said SLM to modulate said light        from said first light source and said light from said second        light source to generate a highlighted imaging beam.        EEE 21. The method of EEE 20, further comprising:    -   sometimes receiving 3D image data and other times receiving 2D        image data; and    -   illuminating said beam steering device with light from said        second light source responsive to receiving said 2D image data.        EEE 22. The method of EEE 20, further comprising modulating said        light from said first light source with a pre-modulator to        generate a modulated illumination beam prior to said step of        illuminating said SLM.        EEE 23. The method of EEE 22, further comprising:    -   combining said modulated illumination beam and said light from        said second light steered by said beam steering device to        generate a combined illumination beam; and    -   said step of illuminating said SLM with light from said first        light source comprises illuminating said SLM with said combined        illumination beam.        EEE 24. The method of EEE 22, further comprising:    -   modeling a light field incident on said SLM based on said        modulated illumination beam; and    -   adjusting said image data based on said modeled light field        prior to asserting said image data on said SLM.        EEE 25. The method of EEE 24, further comprising modeling said        light field incident on said SLM based on said highlight data.        EEE 26. The method of EEE 20, further comprising:    -   illuminating a second SLM configured to have said image data        asserted thereon with light from said second light source; and    -   redirecting at least some of said light from said second light        source to said beam steering device prior to said light from        said second light source reaching said second SLM.        EEE 27. The method of EEE 20, wherein:    -   said step of receiving image data includes sometimes receiving        3D image data and other times receiving 2D image data;    -   said first light source is associated with a first-eye view        present in said image data when said image data comprises 3D        image data;    -   said second light source is associated with a second-eye view        present in said image data when said image data comprises 3D        image data; and    -   said second light source has different spectral characteristics        than said first light source.        EEE 28. The method of EEE 20, wherein said image data comprises        2D image data.        EEE 29. The method of EEE 20, wherein said image data comprises        3D image data.        EEE 30. The method of EEE 20, further comprising polarizing said        highlighted imaging beam.        EEE 31. The method of EEE 30, wherein said step of polarizing        said highlighted imaging beam comprises polarizing said        highlighted imaging beam using a light doubler.        EEE 32. A 3D projection system comprising:    -   an image data input operative to receive 3D image data;    -   a first light source;    -   a second light source;    -   a first projector including        -   a spatial light modulator (SLM) disposed to receive light            from said first light source and being operative to modulate            said light from said first light source based on said 3D            image data to generate a first imaging beam associated with            a first-eye view present in said 3D image data,        -   a controller coupled to receive at least a portion of said            3D image data associated with said first-eye view and being            operative to generate highlight data based on said 3D image            data associated with said first-eye view, to provide said 3D            image data associated with said first-eye view to said SLM,            and to output said highlight data, and        -   a beam steering device coupled to receive said highlight            data from said controller and disposed to receive light from            said second light source, said beam steering device being            operative to steer said light from said second light source            to highlight regions of said SLM based on said highlight            data such that said SLM also modulates light from said            second light source according to said 3D image data            associated with said first-eye view to impart highlights in            said first imaging beam,        -   projection optics disposed in the path of said first imaging            beam and operative to focus said first imaging beam on a            viewing surface, and        -   a first polarization device disposed in the path of said            first imaging beam and being operative to impart a first            polarization state on said first imaging beam;    -   a second projector operative to generate a second imaging beam        associated with a second-eye view present in said 3-D image        data, said second imaging beam having a second polarization        state different than said first polarization state.        EEE 33. The 3D projection system of EEE 32, wherein said second        projector is configured to impart highlights in said second        imaging beam.        EEE 34. The 3D projection system of EEE 32, wherein said first        polarization state is orthogonal to said second polarization        state.        EEE 35. The 3D projection system of EEE 32, wherein said first        polarization device comprises a light doubler.        EEE 36. The 3D projection system of EEE 32, further comprising        3D glasses including a first lens having said first polarization        state and a second lens having said second polarization state.        EEE 37. A method for providing highlighted views in a 3D        projection system, said method comprising:    -   receiving 3D image data to be displayed by a first spatial light        modulator (SLM);    -   generating a first highlighted imaging beam associated with a        first-eye view present in said 3D image data by        -   generating first highlight data based on a portion of said            3D image data associated with said first-eye view,        -   illuminating said first SLM with light from said first light            source,        -   illuminating a beam steering device with light from a second            source,        -   using said beam steering device to steer said light from            said second light source to highlight regions of said first            SLM based on said highlight data, and        -   asserting said 3D image data associated with said first-eye            view on said first SLM to modulate light from said first            light source and light from said second light source to            generate said highlighted imaging beam;    -   polarizing said first highlighted imaging beam in a first        polarization state;    -   generating a second imaging beam associated with a second-eye        view present in said 3D image; and    -   polarizing said second highlighted imaging beam in a second        polarization state different than said first polarization state.        EEE 38. The method of EEE 37, wherein said second imaging beam        includes highlights.        EEE 39. The method of EEE 37, wherein said first polarization        state is orthogonal to said second polarization state.        EEE 40. The method of EEE 37, wherein said step of polarizing        said first highlighted imaging beam comprises polarizing said        highlighted imaging beam using a light doubler.        EEE 41. A method for displaying 2D image data with a 3D        projection system having a first light source associated with a        first-eye view present in 3D image data and a second light        source associated with a second-eye view present in said 3D        image data and having different spectral characteristics than        said first light source, said method comprising:    -   receiving image data to be displayed by a spatial light        modulator (SLM);    -   determining whether said image data comprises 3D image data or        2D image data;    -   asserting said image data on said SLM;    -   illuminating said SLM with light from said first light source;        and    -   if said image data is determined to be 2D image data, causing        said SLM to be further illuminated by light from said second        light source.        EEE 42. A non-transitory, electronically-readable storage medium        having code embodied thereon for causing a 3D projection system        to display 2D image data, said 3D projection system having a        first light source associated with a first-eye view present in        3D image data and a second light source associated with a        second-eye view present in said 3D image data and having        different spectral characteristics than said first light source,        said code being operative to cause said 3D projection system to:    -   receive image data to be displayed by a spatial light modulator        (SLM);    -   determine whether said image data is 3D image data or 2D image        data;    -   assert said image data on said SLM;    -   illuminate said SLM with light from said first light source; and    -   if said image data is determined to be 2D image data, further        illuminate said SLM with light from said second light source.        EEE 43. A method for displaying 2D image data with a 3D        projection system having a first light source associated with a        first-eye view present in 3D image data and a second light        source associated with a second-eye view present in said 3D        image data and having different spectral characteristics than        said first light source, said method comprising:    -   receiving image data to be displayed by a spatial light        modulator (SLM);    -   asserting said image data on said SLM;    -   illuminating said SLM with an illumination beam from one of said        first light source and said second light source;    -   determining whether said image data is 3D image data or 2D image        data; and    -   if said image data is determined to be 2D image data, causing at        least a portion of said illumination beam to be redirected from        said SLM to a second SLM configured to have said 2D image data        asserted thereon.        EEE 44. A non-transitory, electronically-readable storage medium        having code embodied thereon for causing a 3D projection system        to display 2D image data, said 3D projection system having a        first light source associated with a first-eye view present in        3D image data and a second light source associated with a        second-eye view present in said 3D image data and having        different spectral characteristics than said first light source,        said code being operative to cause said 3D projection system to:    -   receive image data to be displayed by a spatial light modulator        (SLM);    -   assert said image data on said SLM;    -   illuminate said SLM with an illumination beam from one of said        first light source and said second light source;    -   determine whether said image data is 3D image data or 2D image        data; and    -   if said image data is determined to be 2D image data, redirect        at least a portion of said illumination beam from said SLM to a        second SLM configured to have said 2D image data asserted        thereon.        EEE 45. A method of manufacturing a projection system, said        method comprising:    -   providing a first light source;    -   providing a second light source;    -   providing a spatial light modulator (SLM) disposed to receive        light from at least one of said first light source and said        second light source and being operative to modulate light to        generate an imaging beam;    -   providing a beam steering device disposed to receive light from        said second light source and being operative to controllably        steer light from said second light source toward selected        regions of said SLM; and    -   providing a beam combiner disposed to receive said light from        said first light source and said steered light from said beam        steering device and being operative to combine said light from        said first light source and said steered light from said second        light source and provide said combined light to said SLM.        EEE 46. The method of EEE 45, further comprising providing a        polarization device disposed in an imaging beam path of said        SLM.

1. A projection system, comprising: a first light source operative toemit a first illumination beam; a second light source operative to emita second illumination beam; a spatial light modulator (SLM) disposed toreceive light from said first light source and being operative tomodulate said light from said first light source based on image data togenerate an imaging beam; a beam steering device disposed to receive atleast a portion of said second illumination beam and being operative tosteer said at least a portion of said second illumination beam tohighlight regions of said SLM based on highlight data such that said SLMalso modulates light from said second light source according to saidimage data to impart highlights in said imaging beam; a second SLMdisposed to receive light from said second light source and operative tomodulate said light from said second light source based on said imagedata to generate a second imaging beam; and a redirector disposed toreceive said second illumination beam and selectively redirect at leastsome of said second illumination beam to said beam steering device priorto light from said second light source reaching said second SLM.
 2. Theprojection system of claim 1, wherein: said first light source comprisesa first set of primary lasers; and said second light source comprises asecond set of primary lights having a different spectral compositionthan said first set of primary lasers.
 3. The projection system of claim1, wherein: said first light source comprises a first white lightsource; said second light source comprises a second white light source;and said first white light source and said second white light sourcecomprise different wavelength bands of red, green, and blue light. 4.The projection system of claim 1, wherein the redirector is configuredto selectively redirect approximately 15% of the second illuminationbeam to said beam steering device.
 5. The projection system of claim 1,wherein the redirector is configured to selectively redirect byswitching between a 2D mode, wherein the redirector is configured toredirect at least some of said second illumination beam to said beamsteering device, and a 3D mode, wherein the redirector is configured topass all of the light of said second illumination beam to said secondSLM.
 6. The projection system of claim 1, wherein said beam steeringdevice comprises a liquid crystal on silicon (LCOS) display or adeformable mirror device (DMD).
 7. The projection system of claim 1,further comprising a pre-modulator disposed in the path of said firstillumination beam and being operative to modulate said firstillumination beam to generate a modulated first illumination beam. 8.The projection system of claim 7, further comprising: a beam combinerdisposed to receive said modulated first illumination beam and said atleast a portion of said second illumination beam and being operative tocombine said modulated first illumination beam and said at least aportion of said second illumination beam to generate a combinedillumination beam and provide said combined illumination beam to saidSLM.
 9. The projection system of claim 8, wherein said beam combinercomprises an optical thin film filter.
 10. The projection system ofclaim 7, further comprising a controller coupled to receive said imagedata and being operative to generate said highlight data based on saidimage data; provide said image data to said SLM; output said highlightdata; model a light field incident on said SLM based on said modulatedfirst illumination beam; and adjust said image data based on said lightfield prior to providing said 2D image data to said SLM.
 11. Theprojection system of claim 10, wherein said controller is furtheroperative to: model said light field incident on said SLM based on saidhighlight data.
 12. The projection system of claim 1, further comprisingan image data input operative to receive said image data, wherein: saidimage data input is configured to receive 3D image data or 2D imagedata; said first light source is associated with a first-eye viewpresent in said image data when said image data comprises 3D image data;said second light source is associated with a second-eye view present insaid image data when said image data comprises 3D image data; and saidsecond light source has different spectral characteristics than saidfirst light source.
 13. The projection system of claim 12, wherein: whensaid image data comprises 2D image data, said controller receives said2D image data and is operative to generate said highlight data based onsaid 2D image data and provide said 2D image data to said SLM; and whensaid image data comprises 2D image data, said SLM modulates said lightfrom said first light source and said light from said second lightsource according to said 2D image data.
 14. The projection system ofclaim 1, further comprising: a polarization device disposed in the pathof said imaging beam and being operative to impart a polarization stateon said imaging beam.
 15. The projection system of claim 14, whereinsaid polarization device comprises a light doubler.
 16. The projectionsystem of claim 1, further comprising projection optics disposed in thepath of said imaging beam and operative to focus said imaging beam on aviewing surface.
 17. A method for displaying an image with a projectionsystem having a first light source and a second light source, saidmethod comprising: illuminating a first spatial light modulator (SLM)with light from said first light source; and illuminating a second SLMwith light from said second light source, redirecting at least some ofsaid light from said second light source to a beam steering device priorto said light from said second light source reaching said second SLM;steering, by said beam steering device based on highlight data of theimage, said redirected light from said second light source to highlightregions of said first SLM; and modulating, by said first SLM based onimage data of the image, said light from said first light source andsaid redirected light from said second light source to generate ahighlighted imaging beam of the image.
 18. The method of claim 17,wherein in a 3D mode, the method comprises the step of passing all ofthe light of said second illumination beam to said second SLM.
 19. Themethod of claim 18, comprising operating in the 2D mode if said imagedata of the image comprises 2D image data and operating in the 3D modeif said image data of the image comprises 3D image data.
 20. The methodof claim 17, wherein: said first light source is associated with afirst-eye view present in said image data when said image data comprises3D image data; said second light source is associated with a second-eyeview present in said image data when said image data comprises 3D imagedata; and said second light source has different spectralcharacteristics than said first light source.
 21. The method of claim17, further comprising: receiving image data of the image to bedisplayed by the first SLM; and generating highlight data based on saidimage data.